package com.adhere.common.utils;

import com.adhere.common.constants.SystemConstants;
import com.adhere.common.pojo.Result;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.util.StringUtils;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import reactor.core.publisher.Mono;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Enumeration;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 *
 * @author WT
 * @date 2022/02/09 09:12:01
 */
public class ServletUtils {

    /**
     * 从 RequestContextHolder 获取 ServletRequestAttributes
     * @return RequestAttributes
     */
    public static ServletRequestAttributes getRequestAttributes() {
        RequestAttributes attributes = RequestContextHolder.getRequestAttributes();
        return (ServletRequestAttributes) attributes;
    }

    /**
     * 获取 request
     */
    public static HttpServletRequest getRequest() {
        return getRequestAttributes().getRequest();
    }

    /**
     * 获取 response
     */
    public static HttpServletResponse getResponse() {
        return getRequestAttributes().getResponse();
    }

    /**
     * 获取 session
     */
    public static HttpSession getSession() {
        return getRequest().getSession();
    }

    /**
     * 获取 String 参数
     */
    public static String getParameter(String name) {
        return getRequest().getParameter(name);
    }

    /**
     * 获取 Integer 参数
     */
    public static Integer getParameterToInt(String name) {
        return TypeConvertUtils.objectToInteger(getRequest().getParameter(name));
    }

    /**
     * 获取 Integer 参数
     */
    public static Integer getParameterToInt(String name, Integer defaultValue) {
        return TypeConvertUtils.objectToInteger(getRequest().getParameter(name), defaultValue);
    }

    public static String getHeader(HttpServletRequest request, String name) {
        String value = request.getHeader(name);
        if (ObjectUtils.isEmpty(value)) {
            return SystemConstants.EMPTY_STR;
        }
        return urlDecode(value);
    }

    public static Map<String, String> getHeaders(HttpServletRequest request) {
        Map<String, String> map = new LinkedHashMap<>();
        Enumeration<String> enumeration = request.getHeaderNames();
        if (enumeration != null) {
            while (enumeration.hasMoreElements()) {
                String key = enumeration.nextElement();
                String value = request.getHeader(key);
                map.put(key, value);
            }
        }
        return map;
    }
//
//    /**
//     * 将字符串渲染到客户端
//     *
//     * @param response 渲染对象
//     * @param string   待渲染的字符串
//     * @return null
//     */
//    public static String renderString(HttpServletResponse response, String string) {
//        try {
//            response.setStatus(200);
//            response.setContentType("application/json");
//            response.setCharacterEncoding("utf-8");
//            response.getWriter().print(string);
//        } catch (IOException e) {
//            e.printStackTrace();
//        }
//        return null;
//    }
//
//    /**
//     * 是否是Ajax异步请求
//     *
//     * @param request
//     */
//    public static boolean isAjaxRequest(HttpServletRequest request) {
//        String accept = request.getHeader("accept");
//        if (accept != null && accept.indexOf("application/json") != -1) {
//            return true;
//        }
//
//        String xRequestedWith = request.getHeader("X-Requested-With");
//        if (xRequestedWith != null && xRequestedWith.indexOf("XMLHttpRequest") != -1) {
//            return true;
//        }
//
//        String uri = request.getRequestURI();
//        if (StringUtils.inStringIgnoreCase(uri, ".json", ".xml")) {
//            return true;
//        }
//
//        String ajax = request.getParameter("__ajax");
//        if (StringUtils.inStringIgnoreCase(ajax, "json", "xml")) {
//            return true;
//        }
//        return false;
//    }
//
    /**
     * 内容编码
     *
     * @param str 内容
     * @return 编码后的内容
     */
    public static String urlEncode(String str) {
        return URLEncoder.encode(str, StandardCharsets.UTF_8);
    }

    /**
     * 内容解码
     *
     * @param str 内容
     * @return 解码后的内容
     */
    public static String urlDecode(String str) {
        return URLDecoder.decode(str, StandardCharsets.UTF_8);
    }

    /**
     * 设置 webflux 模型响应
     *
     * @param response ServerHttpResponse
     * @param value    响应内容
     * @return Mono<Void>
     */
    public static Mono<Void> webFluxResponseWriter(ServerHttpResponse response, Object value) {
        return webFluxResponseWriter(response, HttpStatus.OK, value,HttpStatus.INTERNAL_SERVER_ERROR.value());
    }

    /**
     * 设置webflux模型响应
     *
     * @param response ServerHttpResponse
     * @param code     响应状态码
     * @param value    响应内容
     * @return Mono<Void>
     */
    public static Mono<Void> webFluxResponseWriter(ServerHttpResponse response, Object value, int code) {
        return webFluxResponseWriter(response, HttpStatus.OK, value, code);
    }

    /**
     * 设置webflux模型响应
     *
     * @param response ServerHttpResponse
     * @param status   http状态码
     * @param code     响应状态码
     * @param value    响应内容
     * @return Mono<Void>
     */
    public static Mono<Void> webFluxResponseWriter(ServerHttpResponse response, HttpStatus status, Object value, int code) {
        return webFluxResponseWriter(response, MediaType.APPLICATION_JSON_VALUE, status, value, code);
    }

    /**
     * 设置webflux模型响应
     *
     * @param response    ServerHttpResponse
     * @param contentType content-type
     * @param status      http状态码
     * @param code        响应状态码
     * @param value       响应内容
     * @return Mono<Void>
     */
    public static Mono<Void> webFluxResponseWriter(ServerHttpResponse response, String contentType, HttpStatus status, Object value, int code) {
        response.setStatusCode(status);
        response.getHeaders().add(HttpHeaders.CONTENT_TYPE, contentType);
        Result<?> result = Result.error(code, value.toString());
        byte[] bytes = null;
        try {
            bytes = new ObjectMapper().writeValueAsBytes(result);
        } catch (JsonProcessingException e) {
            e.printStackTrace();
        }
        DataBuffer dataBuffer = response.bufferFactory().wrap(bytes);
        return response.writeWith(Mono.just(dataBuffer));
    }

}
